Modern high-speed aircraft generally have thin wings that provide a low drag profile during high-speed or cruise flight. The wings of these aircraft often include various movable surfaces to provide aircraft control and/or to configure the aircraft for low-speed operations (e.g., takeoff and landing). For example, in addition to carrying fuel, the wings of a high-speed transport aircraft typically included aileron surfaces, spoiler surfaces, leading edge device surfaces, and trailing edge flap surfaces. These movable surfaces are often located at or near the leading and trailing edges of the wing where the wing is too thin to fully enclose the support structure and/or drive mechanisms required to operate these surfaces. Accordingly, fairings are often mounted on the wing to house portions of the drive mechanisms and/or support structure that cannot be enclosed in the wing. These fairings are generally streamlined to have a low drag profile during high-speed or cruise flight.
FIG. 1 is a partially schematic illustration of a transport aircraft 50 having a fuselage 51 with a longitudinal axis L1, a first wing 10a, and a second wing 10b in accordance with the prior art. The first wing includes a movable flap surface 13a and a movable aileron surface 13b. A fairing 20 is mounted on the underside of the first wing 10a to house portions of a support structure and a drive mechanism that are required to operate the flap 13a. The fairing has a longitudinal axis L2 that is at least approximately parallel to the longitudinal axis L1 of the fuselage 51. The fairing 20 has a streamlined planform (e.g., when viewed from the top of the wing) where the widest part relative to the longitudinal axis L2 of the fairing is entirely forward of the trailing edge of the airfoil (e.g., entirely forward of the trailing edge of the flap 13a). However, even these fairings create drag on the aircraft.